Do no trust him.
I posted in Complaint forum but it is not accepted as it is not part of the black market system here.

Note to any future scammers. Do the trade on skype, as long as you don't use the black market system here, you will be safe.
Why? http://i.imgur.com/KGzgT.jpg
What can you do with the police? Tell them you sold gold, something that is illegal already? Get their IP and report to FBI? Same thing as police. Overall, scammer safe, you lose. The end.

Beware of DigitalCorsair06/12/2012 - Diablo 3 Trading - 1 RepliesWe agreed on 11m IGG in Diablo 3 for $100. I gave him 5 mil and he left. Bad manner, as you can tell, so I thought I would just give everybody a heads up. If needed, I can provide screenshots of the Skype conversation, the trade in-game, and the PM he sent me.